As known by those skilled in the art, conventionally, rotary seed dispensers installed in agricultural machines specifically designed for sowing, more commonly known as “planters,” usually comprise a tractor used as a driving unit of the sowing equipment, which, while being driven over the soil to be cultivated sequentially performs the following operations:    a) furrows the soil; b) receives an adequate number of seeds at previously established spacing; and c) revolves the soil again to cover the seeds placed in the furrows.
These planters, in general, have a number of mechanisms to carry out the three basic steps described above; one of such mechanisms is the seed rotary dispenser, where the novelty aspect of the present invention lies and which will be defined later.
The seed rotary dispenser is essentially a tubular housing of circular cross-section of small height assembled underneath a small grain-feeding bin. The seed rotary dispenser is driven at the bottom by a miter gear coupled to the planter driving system which provides rotation to a spinning disc with a number of calibrated orifices (holes) and a ring mounted facing the disc and a passage opening through which the seeds, housed in the disc holes, fall at a given point of the device.
Some rotary dispenser models in conventional equipment, which belong to the state of the art, have radial organizer and expelling devices actuated by springs.
A seed rotary dispenser model, which belongs to the state of the art, is described in patent document PI9701103-7, of the same patent holder, filed on Feb. 27, 1997, under the title “Seed Dosing System for Planting Cereals and Leguminous Plants.”
Seeds deposited in the bin can receive several different treatments, all externally to the small bin, with liquid products and/or particulate solids for several purposes, mixed in mechanical and/or manual ways, which prepare them for sowing.